In order to promote the development of third party applications the 3GPP (Third Generation Partnership Project), which is the stand-ardisation body for third generation mobile system (UMTS), introduced the Open Service Access (OSA) for third generation Mobile System (UMTS). OSA standards are defined in 3GPP, Virtual Home Environment; Open Service Architecture (Release 4). Valbonne, 2001. (3GPP TS 23.127, V4.1.0, 2001-04).
The OSA allows the applications to access the network service capabilities such as Call Control (CC), User Status (US), Messaging (M), Location Information (LI), etc. through open interfaces. Such architecture will certainly play a key role in the realisation of one or more “killer” applications, which is necessary for the success of UMTS. It is worth to stress that nobody knows yet what is going to be such a “killer” application. Indeed, for GSM nobody could predict that SMS (Short Message Service) has become the “killer” application.
OSA is only intended for mobile networks. However, with convergence between telecom and computing, between fixed and mobile, it is crucial that an application is able to operate properly independently of the underlying network. Consequently, it is necessary to extend the coverage of OSA to comprise also other networks than mobile ones such as PSTN/ISDN and also IP-based networks. It is worth noting that IP-based networks may be both wireline and wireless such as for example Wireless LAN (802.11). HiperLAN, or Bluetooth. The situation is depicted in.
Unfortunately, OSA was only intended for mobile networks and it is not specified how to implement OSA for heterogeneous networks. Furthermore, OSA, as specified by the 3GPP, is not sufficient to be applied to heterogeneous networks. The present invention proposes different embodiments to implement OSA on the top of several different networks. Also, additional functionality to OSA is required and proposed by this invention.
According to the knowledge of the inventors, no solution to the problem de-scri-bed above is known at present time. Even for the Parlay Architecture, which OSA is based on, there is no activity of implement-ing Parlay on heterogeneous networks. Although in some overview of the Parlay architecture it is shown a Parlay API covering Mobile networks, ISDN and IP-based network, there is no specification for the implementation.